Bump h2 from 0.3.15 to 0.3.19 in /backend#1

dependabot[bot] wants to merge 1 commit intomainDefGuard/avanguard:mainfrom

dependabot/cargo/backend/h2-0.3.19DefGuard/avanguard:dependabot/cargo/backend/h2-0.3.19Copy head branch name to clipboard